Mechanical behaviour and crack growth studies of gas tungsten arc butt welded joints of 31000-H2 (IS-737) aluminium alloy
Loading...
Date
2015-06
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
G.B. Pant University of Agriculture and Technology, Pantnagar-263145 (Uttarakhand)
Abstract
Welding, as one of the most effective joining methods for metals, has been extensively applied in engineering usage since a long time. The determination of microstructure and mechanical properties of welded structures is thus of paramount importance to implement a damage tolerant approach to structural life extension. In this study, structural and mechanical properties evaluation of 31000-H2 (IS-737) Aluminium Alloy after single pass Tungsten Inert Gas (TIG) welding were investigated to reveal the yield strength, ultimate strength, percentage elongation, impact strength and hardness of welded joints. The TIG Welding results of aluminium alloys 31000-H2 for 5 mm plate thickness using different filler materials during welding are presented. Effect of welding was studied on four different zones such as parent Metal (PM), weld metal (W), heat affected zone (HAZ) and combined zone of base Metal and heat affected zone (W+H).
Welded specimens were investigated using scanning electron microscopy (SEM), UTM and Rockwell micro-hardness tester. Scanning electron microscopy was used to characterize transition sites of welded zone, HAZ, base metal and combined zone of base Metal and heat affected zone. Tensile test was conducted to characterize weld strength by determining ultimate tensile strength and micro-hardness test was conducted to characterize the homogeneity of welding in terms of mechanical properties. Study of the interaction between the cracks and inclusions in thin plates is important in providing a good understanding of mechanical behaviour of structures with defects, and is helpful to the material and structural designs, especially in the fields of modern micro-electronic mechanics and material science. It is well known that interaction of multiple cracks has major influence on the crack growth behaviour. The problem of crack growth analysis in a welded joint containing multiple cracks is one of the major problems, which is not focused in detail by the researchers. This problem in metal represents a complex phenomenon. Hence, the present aim is focused in the experimental investigation of crack trajectory and growth from the single cracks that present in a welded joint. The effect of weld morphology on mechanical response and failure load in commercially available 31000-H2 (IS-737) Aluminium alloy is focused. Crack acceleration, crack coalescence etc. are the part of the present investigation. The purpose of this work is to shed light on some of the experimental
observations and computational concerns on crack growth due to presence of single crack in a welded component under tensile, shear, pull out modes.
Description
Thesis-PhD
Keywords
sowing, biological phenomena, diseases, application methods, pathogens, fungi, planting, germinability, crops, irrigation